带参数Coons插值曲面的图像插值方法

提出一种根据图像边缘特征调整插值曲面形状的图像插值方法．首先把数字图像构造为分片双三次Coons曲面；然后引入曲面形状控制参数，调整曲面的形状以符合图像的边缘特征；最后对插值曲面进行重采样．实验结果表明，该方法可以大大改善传统图像插值方法的平滑作用，保持插值图像边缘清晰、光滑。

Image Interpolation Using Coons Surface Patch with Shape Control Parameters

Piecewise bicubic Coons surface patch with adjustable parameters to modify the length and direction of tangent vector at some control points is constructed for a digital image. Boundary curves are first adjusted to fit the image edges. Then the U-V tangent vectors at interior control points and twist vectors at corner points of the surface patch are adjusted to fit the whole image. Such an approach can counteract the smoothing effect of traditional methods greatly and keep the image edges still sharp and smooth.